The COP is similar to the thermal efficiency for a heat pump in that it is a ratio of what you get (energy delivered to the interior of the building) to what you give (work input).
Because QH is generally greater than Win, typical values for the COP are greater than 1.
It is desirable for the COP to be as high as possible.
Example: if the COP for a heat pump is 4, the amount of energy transferred to the building is 4 times greater than the work done by the motor in the heat pump.